Device for the promotion of chimney intake



March 13, 1951 A. BURGER DEVICE FOR THE PROMOTION OF CHIMNEY INTAKE s Sheets-Shet. 1

Filed May 31, 1945 INVENTOR ATTORNEYS A. BURGER DEVICE FOR THE PROMOTION OF CHIMNEY INTAKE March 13, 1951 5 Sheets-Sheet 2 Filed May 51, 1945 AT TO RNEYS March 13, 1951 A. BURGER 2,544,776

DEVICE FOR THE PROMOTION OF CHIMNEY INTAKE Filed May 51, 1945 3 Sheets-Sheet 3 Fig.3.

INVENTOR ARMIN BURGER ATTORNEYS Patented Mar. 13, 1951 DEVICE. FOR THE PROMOTION OF CHIMNEY IN TAKE Armin Burger, Wabcr'n-Eerne, Switzerland.

Application May 31, 1945, Serial No. 596,962- In Switzerland December 5, 1944 2' Claims. (01. 98-78).

This invention relates to a device for the promotion of chimney intake.

The air-current of the chimney, as is well known, is affected detrimentally by the action of the wind on the chimney aperture and on the warmth of the air, so that chimneys have been provided with cowls which turn with the wind and prevent any down-draught. These metal cowls are attacked by the. heating gases and are not reliable. Even the covering of the mouth of the chimney by means of sheets does not bring about the desired result.

The present invention relates to a cowl for chimneys of the kind comprising superposed hollow rectangular sections and curved passages for air formed between ad acent sections, said passages pas ing upwardly and inwardly towards the central vertical axis of the chimney and being of increasing cross-section: towards sa d central axis. It is characteri ed in. that the said pa sages are arranged vertically one above the other and in that the bounding lines of their curved surfaces lying respectively in vert cal plane containing the central axis of the chimney, if cont nued. converge on one another and on t e s id central ax s at a point above the chimney. whereby the air currents led to the interior of the cowl by the aid pa sages are concentrated onto the central part: thereof and better extraction of the gases from. the chimney is obtained.

' Prefera ly the uppermost passage is wider in cros section than the passa es lower down and the inter or cross-sect onof the uppermostpart is la ger than that. of the chimney cross-section and of t at of the parts situated beneath it.

A body of substantially lozenge-shaped crosssection can be provided in the central opening of the uppermost rectangular section of the cowl, the two upper surfaces of which body have a slightly concave curvature and lie substantially parallel to the lines of curvature of those passages situated at the corresponding side of the cowl.

In the drawing some embodiments of the invention are illustrated by way of example.

Fig. 1 shows a diagrammatic view of the upper portion of a chimney with the cowl device fitted to it.

Fig. 2 is a plan of Fig. 1. r

In Fig. 3, is a vertical section of Fig. 1, showing an upward current of air.

Fig. 4 shows in perspective, the same embodiment as in Fig. 3, but when a gentle side wind enters from above.

Fig. 5 shows: in: perspective the same embodiment as in Figs. 3- or lbutwhen a Wind enters perpendicularly from above.

The drawings" show the three, uppermost courses I of bricks of a chimney upon which is placed a section 2,. the interior of which is filled with. filling material 4 such as cement, up to the upper edge 3 on which is: the interior cross-section of the chimney. Above this lie two further similar body sections 5: and. 6, which are kept at a: distance from. each; other by means of props I at thefour corners. Upon the body section 6 is fixed an upper body section 8 forming the top and. whose interior cross-sectionat 9 is. larger than the interior cross-section of the. chimney itself, being convenientlyso much larger as to correspond with the increase in volume of the flue-gas. by the volume of air which enters through the passages l5, l6..

An essential characteristic of" the present inventionis, that thecurvedxpassages l5, l6, formed between two adjacent sections extend upwardly atan acute angle towards the axisof the chimney A-B and. that they flare increasingly towards the interior of'the chimney, that is towards the axis: AB,. as can be seen from the drawing. The passages: l5; [6, are therefore narrower in height on the outside in the neighbourhood of the props! than at the inner upper edges 3-, f0 and II as well as being curved and convex towards the axis of the chimney AB, as may be observed in particular from Fig. 2. a The upper edges 3, ID, H are therefore not straight lines, but lines arched towards the axis of the chimney. Moreover, the cross-section of the uper passage [6, which is formed by the upperpart 8 and the part 6 situated beneath it, is larger than the cross-section of the lower passage l5.

With rising winds, the air current, as can be seen from Fig. 3, blows upwards through the passages l5, [6, as indicated by the arrows, and imparts an additional draught to the flue-gases. If the wind strikes from the side, somewhat obliquely from above, against the cowl according to the present invention, it penetrates, as is illustrated in Fig. 4, into the passages I5, I6, is directed upwards and likewise imparts an additional upward speed to the smoke. currents striking perpendicularly upon the chimney no disturbance of the intake of the chimney, but an improvement in lift, is obtained, as is shown in Fig. 5. Here too, the wind currents, which is represented by arrows strike directly on to the interior cross-section of the upper rim 9,

But even with eddy hit the inserted body 12 and are diverted sideways into the uppermost passage I6. Since this uppermost passage l6 and the interior cross-section of the upper body 9 are larger than the subjacent passage 15 and the cross-section of the bodies 19 and l I, no back-pressure occurs, but, as shown by practical tests a lift enters the passage I6, so that the draught is not affected.

The same thing occurs when an eddy current occurs, as is shown in Fig. 5, so that in any event a suction of the flue-gases is attained. According to the present invention, the drawback that the chimney does not draw in warm weather because the specifically heavier column of fluegases in the chimney has no lift against the lighter outside air, is also obviated. The warm outside air rises through the section passage like the upward current in Fig. 3 and creates a draught which is all thestronger the greater the difference in temperature between the outside air and the inside air. These facts have been confirmed by means of comprehensive practical experiments.

According to a particular embodiment of the invention, a streamlined body, e. g. a prism I2, is fixed on the rim 9 of the uppermost section 8 by means of a shoulder l4 having suitably spherically curved side surfaces l3. The prism '12 should conveniently be situated so that its upper edge points from south to north, if, as is most often the case, east or west winds prevail in the neighbourhood. Even the most piercing eddy wind is then so diverted, that it never blows into the fireplace, but always creates an additional draught which increases with the strength of the wind. Consequently this embodiment is particularly suited to firing installations which can only have a short chimney, as e. g., land or water vehicles, or in the case of buildings in the mountains, at the edge of a wood and so on, where rather strong eddy winds are frequently to be reckoned with.

In consequence of the increase in draught obtained at any state of the wind and weather by means of the arrangement according to the present invention, not only is a faultless action of the firing installation obtained, but also a saving in fuel, since the temperature of the flue-gas may, as a result of the creation of additional draught, be lower than is usually requisite for the creation of the necessary lift. The slight expenditure for the fixing of the new section arrangement is therefore outweighed, after a short time, by the saving of fuel.

Patent claim.

1. Cowl for chimneys, of the kind comprising superposed hollow rectangular sections and curved passages for air formed between adjacent sections, said passages passing upwardly and inwardly towards the central vertical axis of the chimney and being of increasing cross-section towards said central axis, characterised in that the said passages are arranged vertically one above the other and in that the bounding lines of their curved surfaces lying respectively in vertical planes containing the central axis of the chimney, if continued, converge on one another and on the said central axis at a point above the chimney, whereby the air currents led to the interior of the cowl by the said passages are concentrated onto the central part thereof and better extraction of the gases from the chimney is obtained.

2. Cowl for chimneys, as claimed in claim 1, wherein the central opening of the uppermost rectangular section is larger than those of the remaining sections and has a transverse deflector of lozenge-shaped cross-section inserted therein, said deflector having two upper concave surfaces which lie along the lines of curvature of those passages situated at the corresponding side of the cowl, whereby the air currents led to the interior of the cowl by the said passages are concentrated onto the central part thereof and better extraction of the gases from the chimney is obtained.

ARMIN BURGER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 744,570 Le Beau Nov. 17, 1903 1,549,813 Spring et al Aug. 18, 1925 FOREIGN PATENTS Number Country Date 20,438 Great Britain A. D. 1912 103,333 Great Britain Jan. 22, 1917 367,721 Great Britain Feb. 25, 1932 707,645 France Apr. 20, 1931 311,999 France Jan. 27, 1937 846,595 France June 12, 1939 147,743 Germany Feb. 3, 1904 551,966 Germany June 8, 1932 576,476 Germany May 13, 1933 31,270 Switzerland Aug. 19, 1904 102,208 Switzerland Nov. 16, 1923 113,114 Switzerland Dec. 16, 1925 

